Average of two elements in a vector that have specific index

Hi all,

I have a vector where each two elements corresponds to a group, so as a result there are four goups and in each there are two numbers, as shown below in the image:

I want to compute the averge of ith-element of each group and store the answer in a new vector. For example, the averge of the first element from each gorup (the red circles) is 4, as shwon above. The resulting vector should be in size.

%Define the number of elements in each group
NoElements = 2;
%Define the number of groups
NoGroups = 4;
%Define the vector
A =[1
    2
    3
    4
    5
    6
    7
    8];
%perform the averaging
for j = 1:NoElements
    A_ave(j) = ?
end    

Any help would be appreicted.

Answer 1

[Shivam]

Hi,

To compute the average of the (i)-th element from each group and store the result in a new vector, you can follow these steps in MATLAB. Here's how you can do it:

1. Understand the Data Structure: Since you have a vector A where each two elements correspond to a group, you can reshape the vector into a matrix where each column represents a group.
2. Calculate the Average: Use the mean function to compute the average of each row, which corresponds to the (i)-th element across all groups.

Here's the MATLAB code to achieve this:

% Define the number of elements in each group
NoElements = 2;

% Define the number of groups
NoGroups = 4;

% Define the vector
A = [1; 2; 3; 4; 5; 6; 7; 8];

% Reshape the vector into a matrix where each column represents a group
A_matrix = reshape(A, NoElements, NoGroups);

% Perform the averaging
A_ave = mean(A_matrix, 2);

% Display the result
disp('Averaged vector:');
disp(A_ave);

Hope it helps.